Field of the Invention
The present invention relates to vehicular AC generators mounted on vehicles and the like.
Description of the Related Art
Patent Document 1 describes, as an example of a conventional vehicular AC generator, a configuration of a brush holder including a positive brush, a negative brush, a casing, a positive terminal and a negative terminal, in which the negative terminal connected to the negative brush is fastened together with a housing frame at a regulator-case-fixing hole portion, directly or with a metal pipe press-fitted or insert-molded in the portion; meanwhile the positive terminal is connected and fixed to a regulator control terminal.
On the other hand, Patent Document 2 describes that in a rectifier that is another component similarly fixed to a projecting boss of a frame (bracket), if the entire rectifier is supported only by part of a negative-side cooling fin and the projecting boss of the frame, the fin undergoes excessive stress due to vehicle vibration, causing such problems as the fin deforming and the longevity of mounted rectifying elements shortening; therefore, as a countermeasure against this problem is shown a configuration in which all stacking members including the negative-side cooling fin are fastened together with the frame, so as to relieve a burden imposed on the fin. In addition, it is described that in a stacking construction such as this, a large assembling step is created that is comparable to accumulated tolerance of the rectifier made up of the stacking members including a terminal base, a positive-side cooling fin and an insulating spacer. Furthermore, it is also described that if the problem with the assembling step as described above is left unsolved, there arises another problem in that diodes are likely to undergo excessive stress due to distortion caused in the fin close to a directly fixing portion during assembly to fix, and their longevity would be thereby shortened, and in order to solve this problem, a low-rigid portion is provided close to the directly fixing portion.    Patent Document 1: Japanese Patent No. 3812822    Patent Document 2: Japanese Patent No. 3543876
Patent document 2 describes a problem attributed to a large assembling step created in components provided with both fastening-together portions and component-fixing portions, and this problem is known to arise in other components such as conventional brush holders, so it is difficult to eliminate the large assembling step itself comparable to the tolerance of the stacking members. Incidentally, “the large assembling step comparable to tolerance of the stacking members” described in this description is as follows: for example, when all stacking components are dimensionally at their respective upper limits or at lower limits within allowable tolerance of the respective components to be assembled, the limits accumulate, which could lead to the stacking members exceeding an allowable range. This is expressed as “the large step.”
As to locations (terminals) at which the brush holder is fixed to other components or the frame, in Patent Document 1, not all of the locations are arranged on the same plane perpendicular to the rotation shat, and on one plane, a location is moved outwardly farther than the outer peripheral end of the brush holder case. By configuring as described above, vibration in the rotation axis direction due to rotation of the rotor under high-vibration conditions should be prevented. However, since the foregoing step is created when the brush holder is assembled, in fact, not so small distortion is imposed on the terminal portion extending relatively long. In the worst case, the extending portion may break off at the base, so that there has been a fear of insulation being not assured.
Moreover, since the low-rigid portion is provided close to the fixing portion in Patent Document 2, there have been problems with destabilizing factors, such as components wobbling when they are fixed, mechanical strength and so forth.